Fern Grotto

Useful Information

Location: Wailua River, Kauai.
Hwy. 56, first turn right after the river from the north, from south 1.6 km after the Wailua Golf Course turn left just before crossing the bridge. Signposted for Wailua Marina State Park.
(22° 2'20.59"N, 159°21'33.32"W)
Open: All year daily 9-15:30.
Boats leave every 30mins.
Fee: Adults USD 20, Children (2-12) USD 10.
Online Discount Prices: Adults USD 18, Children (2-12) USD 9.
Classification: SpeleologyLava Cave
Light: LightIncandescent Electric Light System
Guided tours: D=80 min, V=125,000/a.
Address: Fern Grotto, Smiths Tropical Paradise, Smith's Motor Boat Service Inc., Tel: +1-808-821-6895.
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then.
Please check rates and details directly with the companies in question if you need more recent info.


1946 first tours to Fern Grotto State Park by Walter Smith, Sr. and his wife, Emily.
1968 start of boat tours by the Waialeale family.
2001 Lihue Plantation closed.
AUG-2004 Waialeale Boat Tours evicted from river because of unpaid back rent to the state.


This is not a cave, it is a grotto, it is Fern Grotto. In speleology, the science about caves, caves are of natural origin, and grottos are artificial, shallow, and covered by kitschy rocks, minerals and shells. So if we should choose, we would also call it a grotto.

Fern Grotto is a major tourist draw on the island Kauai. It is located at Wailua River, right in the middle of the east coast. To reach it, the visitor board a ship and are carried 15 minutes upstream to a pier. From here its five minutes pleasant stroll to the grotto. The first impression is a sort of amphitheatre, with steep, green walls. We guess the cave is a river cave formed in a soft layer of lava by the river. An overhanging cliff which works pretty well as a natural shelter. The tropic climate and the regular rains allow an abundant plant growth, which makes this place pretty comfortable.

However, the sight is at least partly artificial as a plantation-created reservoir above the cave caused a steady flow of water. This water supply allowed the growth of ferns on the ceiling of the cave. But the closing of the sugar plantations has ended the water supply. This change and damages caused by two recent hurricanes required a refurbishing of the cave by the Hawaii Tourism Authority and Kauai County at the cost of $440,000.

However, as an attraction this cliff cave is much too boring, so the management invented the whole entertainment stuff to make the visit more impressive. The boat ride, hula music during the ride, marriages in the grotto, more music at the cave, smiling people everywhere. Pretty creepy. If you are not afraid of such things, go to Fern Grotto and enjoy.